Resolving system information between EPS and 5GS

ABSTRACT

According to some embodiments, a method for use in a wireless device of acquiring system information associated with a core network comprises receiving system information from a network node. The network node is connected to one or more core networks. The system information includes an indication of a network type (e.g., enhanced packet system (EPS), fifth generation system (5GS), etc.) for each core network. The method further comprises determining a capability of the wireless device for connecting to the plurality of network types, and determining whether to connect to a core network based on the network type and the capability of the wireless device. In particular embodiments, the indication of the network type comprises a list of public land mobile networks (PLMNs) connected to the network node and an indication of network types supported by each PLMN.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/483,434, filed Aug. 5, 2019, which is a 371 of PCT/IB2018/050607,filed Jan. 31, 2018, which claims the benefit of U.S. ProvisionalApplication No. 62/454,710, filed Feb. 3, 2017, the disclosures of whichare fully incorporated herein by reference.

TECHNICAL FIELD

Certain embodiments of the present disclosure relate, in general, towireless communications and, more particularly, to resolving ambiguityin system information (SI) broadcast in cells that support one or moreof Third Generation Partnership Project (3GPP) evolved packet system(EPS) and fifth generation system (5GS) core networks.

INTRODUCTION

The standardization organization Third Generation Partnership Project(3GPP) is currently specifying a new radio interface referred to as newradio (NR), fifth generation (5G), 5G-NR, or next generation universalterrestrial radio access (G-UTRA), as well as a next generation packetcore network (NG-CN, NGC, 5GC, or 5G-CN). Below is a brief descriptionbased on 3GPP TS 23.799 v1.1.0 (incorporated herein by reference), whichincludes a high-level architecture for a next generation system (NGS).

FIG. 1 is a block diagram illustrating a high level architecture of a 5Gsystem. The illustrated architecture may be used as a reference modelfor processes described herein. FIG. 1 includes next generation userequipment (UE) 10, next generation radio access network (RAN) 20, nextgeneration core network 30 and their reference points. Next generationRAN 20 (also referred to as 5G-RAN) may include different radio basestations (e.g., long term evolution (LTE) eNBs and NR gNB).

Next generation UE 10 is coupled to a next generation RAN 20. Nextgeneration RAN 20 is coupled over a communication path NG2 or NG3 tonext generation CN 30 that in turn is coupled to data network 40, suchas the Internet. NG1 represents a reference point for the control planebetween next-generation UE 10 and next-generation CN 30. NG2 representsa reference point for the control plane between next generation RAN 20and next generation CN 30. NG3 represents a reference point for the userplane between next generation RAN 20 and next generation CN 30. NG6represents a reference point between next generation CN 30 and datanetwork 40. Data network 40 may be an operator external public orprivate data network or an intra-operator data network (e.g., forprovision of IP Multimedia Subsystem (IMS) services. NG6 corresponds toSGi for 3GPP accesses. SGi is the reference point for the interfacebetween the packet data network (PDN) gateway (GW) and the packet datanetwork (PDN).

Network deployments based on different 3GPP core networks (e.g.,EPC-based and 5GC-based) and UEs with different capabilities (e.g.,EPC-NAS and 5GC-NAS) may coexist at the same time within one public landmobile network (PLMN). An example is described in the 3GPP submissionS2-170673, entitled “Migration-Architecture,” Qualcomm Inc., SA2#118bis, which is incorporated herein by reference. A UE that is capableof supporting 5GC-NAS procedures may also be capable of supportingEPC-NAS procedures. Therefore, UEs that are capable only of EPC-NAS mustbe connected to EPC, while UEs that are capable of 5GC-NAS can beconnected either to EPC or 5GC.

A LTE eNB can belong to multiple PLMNs (e.g., for RAN network sharing).For each PLMN, the LTE eNB can be connected to: (1) EPC only, (2) 5GConly, or (3) both EPC and 5GC. This may be because different operatorsmay introduce support for 5GC at different times.

A LTE eNB may broadcast information about which core networks areavailable on each PLMN to assist the different UEs in performing corenetwork selection. Thus, LTE system information (SI) may be extended toprovide information about the available core networks for each PLMN. Anextension to the system information should ensure backwardcompatibility. For example, the extension may ensure that UEs capableonly of EPC-NAS can be connected to EPC and thus served by EPS. For anLTE eNB that is connected to 5GC only, the UEs only capable of EPC-NASshould be barred and should reselect to a different cell.

The current version of the SystemInformationBlock1 andSystemInformationBlock2 are presented below for reference.

A problem with existing system information is that system information incells serving both EPS and 5GS should ideally be backwards compatible sothat the cell can serve legacy UEs connected to EPC/EPS. On the otherhand, because radio resources are scarce, designing new and separate SIfor UEs connected to 5GC and served by 5GS is not acceptable. Thisaffects the information about network configuration and its capabilitiesacquired by UEs via SI because the information may become ambiguous withrespect to its validity in EPS and 5GS. Two examples are brieflydiscussed below.

For shared RAN (Multi Operator Core Network support, see TS 23.512), acell broadcasts in the SI a list of operators sharing the cell listed asPLMNs. At registration (Attach), a UE indicates to the RAN its selectedPLMN. At the selection process though, the UE cannot determine whetherthe selected PLMN is supported in 5GS as well as in EPS, or in only oneof the systems.

Similarly, other broadcasted network capabilities (e.g., multimediabroadcast multicast services (MBMS), access barring, etc.) may beambiguous with respect to their applicability on the system level (i.e.,whether they are applicable in the same level in EPS as well as in 5GS).This may result in a UE receiving ambiguous information, resulting in aUE that may make incorrect determinations and be misaligned with thenetwork configuration.

SUMMARY

Certain embodiments include a radio access network (RAN)/cell thatindicates in its system information (SI) the applicability of particularsystem information to fifth generation system core (5GSC) networks,where a user equipment (UE) may unambiguously identify the particularsystem information as valid in evolved packet system (EPS) or fifthgeneration system (5GS).

For example, with respect to a shared RAN, system information mayindicate whether a public land mobile network (PLMN) supports 5GS. Someembodiments may facilitate future long term evolution (LTE) cells thatonly support 5GS. Particular embodiments include using existingparameters to bar the cell for operator use which prevents legacy UEsfrom camping or connecting to the cell. New UEs supporting 5GS ignorethe parameter. Particular embodiments use a new parameter to indicate ifthe cell is also barred for UEs that support 5GS.

According to some embodiments, a method for use in a wireless device ofacquiring system information associated with a core network comprisesreceiving system information (e.g., system information block one (SIB1),system information block two (SIB2), etc.) from a network node. Thenetwork node is connected to one or more core networks. The systeminformation includes an indication of a network type (e.g., EPS, 5GS,etc.) for each core network. The method further comprises determining acapability of the wireless device for connecting to the plurality ofnetwork types, and determining whether to connect to a core networkbased on the network type and the capability of the wireless device. Inparticular embodiments, the indication of the network type comprises alist of PLMNs connected to the network node and an indication of networktypes supported by each PLMN.

In particular embodiments, determining whether to connect to a corenetwork comprises determining not to connect to any of the one or morecore networks, and the method further comprises connecting to adifferent network node.

In particular embodiments, determining the capability of the wirelessdevice for connecting to the plurality of network types comprisesdetermining the wireless device is capable of connecting to a 5GS corenetwork type, and the method further comprises interpreting one or moreparameters of the received system information differently for 5GS thanfor EPS (e.g., ignore EPS barring parameter in favor of 5GS barringparameter). Interpreting one or more parameters of the received systeminformation differently for 5GS may comprise obtaining an indication(e.g., receiving dedicated or broadcast signaling from the network node)that one or more information elements of the system information are tobe interpreted according to 5GS. Obtaining the indication that one ormore information elements are to be interpreted according to 5GS maycomprise determining that the wireless device is connected to a 5GS corenetwork.

In particular embodiments, determining the capability of the wirelessdevice for connecting to the plurality of network types comprisesdetermining the wireless device is capable of connecting to a 5GS corenetwork type, and the method further comprises acquiring 5GS specificsystem information blocks.

According to some embodiments, a wireless device is capable of acquiringsystem information associated with a core network. The wireless devicecomprises processing circuitry operable to receive system information(e.g., SIB1, SIB2, etc.) from a network node. The network node isconnected to one or more core networks. The system information includesan indication of a network type (e.g., EPS, 5GS, etc.) for each corenetwork. The processing circuitry is further operable to determine acapability of the wireless device for connecting to the plurality ofnetwork types, and determine whether to connect to a core network basedon the network type and the capability of the wireless device forconnecting to the plurality of network types. In particular embodiments,the indication of the network type comprises a list of PLMNs connectedto the network node and an indication of network types supported by eachPLMN.

In particular embodiments, the processing circuitry determines not toconnect to any of the core networks, and the processing circuitry isfurther operable to connect to a different network node.

In particular embodiments, the processing circuitry determines thewireless device is capable of connecting to a 5GS core network type, andthe processing circuitry is further operable to interpret one or moreparameters of the received system information differently for 5GS thanfor EPS (e.g., ignore EPS barring parameter in favor of 5GS barringparameter). The processing circuitry may be operable to interpret one ormore parameters of the received system information differently for 5GSby obtaining an indication (e.g., receiving dedicated or broadcastsignaling from the network node) that one or more information elementsof the system information are to be interpreted according to 5GS. Theprocessing circuitry may be operable to obtain the indication that oneor more information elements are to be interpreted according to 5GS bydetermining that the wireless device is connected to a 5GS core network.

In particular embodiments, the processing circuitry determines thewireless device is capable of connecting to a 5GS core network type, andthe processing circuitry is further operable to acquire 5GS specificsystem information blocks.

According to some embodiments, a method for use in a network node ofproviding system information associated with a core network comprisesdetermining the network node is connected to one or more core networks,and transmitting system information (e.g., SIB1, SIB2, etc.). The systeminformation includes an indication of a network type (e.g., EPS, 5GS,etc.) for each core network. The indication of the network type maycomprise a list of identifiers of one or more PLMNs connected to thenetwork node and an indication of one or more network types supported byeach PLMN.

In particular embodiments, a core network of the one or more corenetworks is a 5GS core network. The system information for the corenetwork includes parameters that have a different meaning with respectto 5GS than with respect to EPS. The system information may include 5GSspecific system information blocks.

In particular embodiments, the method further comprises transmitting anindication (e.g., dedicated signaling or broadcast signaling) that oneor more information elements of the system information are to beinterpreted according to 5GS.

According to some embodiments, a network node is capable of providingsystem information associated with a core network. The network nodecomprises processing circuitry operable to determine the network node isconnected to one or more core networks, and transmit system information(e.g., SIB1, SIB2, etc.). The system information includes an indicationof a network type (e.g., EPS, 5GS, etc.) for each core network of theone or more core networks. The indication of the network type maycomprise a list of identifiers of one or more PLMNs connected to thenetwork node and an indication of one or more network types supported byeach PLMN.

In particular embodiments, a core network of the one or more corenetworks is a 5GS core network. The system information for the corenetwork includes parameters that have a different meaning with respectto 5GS than with respect to EPS. The system information may include 5GSspecific system information blocks.

In particular embodiments, the processing circuitry is further operableto transmit an indication (e.g., dedicated signaling or broadcastsignaling) that one or more information elements of the systeminformation are to be interpreted according to 5GS.

According to some embodiments, a wireless device is capable of acquiringsystem information associated with a core network. The wireless devicecomprises a receiving module and a determining module. The receivingmodule is operable to receive system information from a network node.The network node is connected to one or more core networks. The systeminformation includes an indication of a network type for each corenetwork of the one or more core networks. The determining module isoperable to determine a capability of the wireless device for connectingto the plurality of network types, and determine whether to connect to acore network of the one or more core networks based on the network typeof the core network and the capability of the wireless device forconnecting to the plurality of network types.

According to some embodiments, a network node is capable of providingsystem information associated with a core network. The network nodecomprises a determining module and a transmitting module. Thedetermining module is operable to determine the network node isconnected to one or more core networks. The transmitting module isoperable to transmit system information. The system information includesan indication of a network type for each core network of the one or morecore networks.

Also disclosed is a computer program product. The computer programproduct comprises instructions stored on non-transient computer-readablemedia which, when executed by a processor, perform the steps of:receiving system information from a network node that is connected toone or more core networks of a particular network type (e.g., EPS, 5GS,etc.); determining a capability of the wireless device for connecting toa plurality of network types, and determining whether to connect to acore network based on its network type and the capability of thewireless device.

Another computer program product comprises instructions stored onnon-transient computer-readable media which, when executed by aprocessor, perform the steps of determining the network node isconnected to one or more core networks, and transmitting systeminformation (e.g., SIB1, SIB2, etc.). The system information includes anindication of a network type (e.g., EPS, 5GS, etc.) for each corenetwork.

Certain embodiments of the present disclosure may provide one or moretechnical advantages. For example, in some embodiments a UE canunambiguously interpret the content of the system information whenacquiring system information from a cell serving EPS and 5GSsimultaneously. This may avoid incorrect UE understanding of networkcapabilities. Particular embodiments that indicate support for 5GC on aper PLMN basis facilitate different operators sharing the same RAN node.Upgrading to 5GC support may be performed at different times. Requiringall operators to upgrade at the same time is more challenging, and thusundesirable. Certain embodiments may have none, some, or all of therecited advantages.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the embodiments and their featuresand advantages, reference is now made to the following description,taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating a high level architecture of a 5Gsystem;

FIG. 2 is a block diagram illustrating an example wireless network,according to a particular embodiment;

FIG. 3 is a flow diagram of an example method in a user equipment,according to some embodiments;

FIG. 4 is a flow diagram of an example method in a network node,according to some embodiments;

FIG. 5A is a block diagram illustrating an example embodiment of awireless device;

FIG. 5B is a block diagram illustrating example components of a wirelessdevice;

FIG. 6A is a block diagram illustrating an example embodiment of anetwork node; and

FIG. 6B is a block diagram illustrating example components of a networknode; and

FIG. 7 is a block diagram illustrating an example embodiment of a corenetwork node.

DETAILED DESCRIPTION

As described in the Introduction, Third Generation Partnership Project(3GPP) is currently specifying fifth generation (5G) new radio (NR) anda next generation packet core network (NG-CN, NGC, 5GC, or 5G-CN).Network deployments based on different 3GPP core networks (e.g., evolvedpacket core (EPC)-based and 5GC-based) and user equipment (UEs) withdifferent capabilities (e.g., EPC-NAS and 5GC-NAS) may coexist at thesame time within one public land mobile network (PLMN). A UE that iscapable of supporting 5GC-NAS procedures may also be capable ofsupporting EPC-NAS procedures. Therefore, UEs that are capable only ofEPC-NAS must be connected to EPC, while UEs that are capable of 5GC-NAScan be connected either to EPC or 5GC.

A long term evolution (LTE) eNB can belong to multiple PLMNs (e.g., forRAN network sharing). For each PLMN, the LTE eNB can be connected to:(1) EPC only, (2) 5GC only, or (3) both EPC and 5GC. This may be becausedifferent operators may introduce support for 5GC at different times.

A LTE eNB may broadcast information about which core networks areavailable on each PLMN to assist the different UEs in performing corenetwork selection. Particular embodiments may extend the LTE systeminformation (SI) to provide information about the available corenetworks for each PLMN. Particular embodiments ensure backwardcompatibility. For example, particular embodiments ensure that UEscapable only of EPC-NAS can be connected to EPC and thus served by EPS.For an LTE eNB that is connected to 5GC only, the UEs only capable ofEPC-NAS may be barred and may reselect to a different cell.

Certain embodiments include a radio access network (RAN)/cell thatindicates in its SI the applicability of particular system informationto 5GS networks, where a UE may unambiguously identify the particularsystem information as valid in evolved packet system (EPS) or fifthgeneration system (5GS).

For example, with respect to a shared RAN, system information mayindicate whether a PLMN supports 5GS. Some embodiments may facilitatefuture LTE cells to only support 5GS. Particular embodiments includeusing existing parameters to bar the cell for operator use whichprevents legacy UEs from camping or connecting to the cell. New UEssupporting 5GS ignore the parameter. Particular embodiments use a newparameter to indicate if the cell is also barred for UEs that support5GS.

In some embodiments, a UE can unambiguously interpret the content of thesystem information when acquiring system information from a cell servingEPS and 5GS simultaneously. This may avoid incorrect UE understanding ofnetwork capabilities. Particular embodiments that indicate support for5GC on a per PLMN basis facilitate different operators sharing the sameRAN node. Upgrading to 5GC support may be performed at different times.Requiring all operators to upgrade at the same time is more challenging,and thus undesireable.

References in the specification to “one embodiment,” “an embodiment,”“an example embodiment,” etc., indicate that the embodiment describedmay include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to implement such feature, structure, orcharacteristic in connection with other embodiments, whether or notexplicitly described.

Generally, all terms used herein are to be interpreted according totheir ordinary meaning in the technical field, unless explicitly definedotherwise herein. All references to “a/an/the element, apparatus,component, means, step, etc.” are to be interpreted openly as referringto at least one instance of the element, apparatus, component, means,step, etc., unless explicitly stated otherwise. The steps of any methoddisclosed herein do not have to be performed in the exact orderdisclosed, unless explicitly stated.

Particular embodiments are described with reference to FIGS. 2-7 of thedrawings, like numerals being used for like and corresponding parts ofthe various drawings. LTE and NR are used throughout this disclosure asexample cellular systems, but the ideas presented herein may apply toother wireless communication systems as well.

FIG. 2 is a block diagram illustrating an example wireless network,according to a particular embodiment. Wireless network 100 includes oneor more wireless devices 110 (such as mobile phones, smart phones,laptop computers, tablet computers, MTC devices, or any other devicesthat can provide wireless communication) and a plurality of networknodes 120 (such as base stations or eNodeBs). Network node 120 servescoverage area 115 (also referred to as cell 115).

In general, wireless devices 110 that are within coverage of radionetwork node 120 (e.g., within cell 115 served by network node 120)communicate with radio network node 120 by transmitting and receivingwireless signals 130. For example, wireless devices 110 and radionetwork node 120 may communicate wireless signals 130 containing voicetraffic, data traffic, and/or control signals. A network node 120communicating voice traffic, data traffic, and/or control signals towireless device 110 may be referred to as a serving network node 120 forthe wireless device 110.

In some embodiments, wireless device 110 may be referred to by thenon-limiting term “UE.” A UE may include any type of wireless devicecapable of communicating with a network node or another UE over radiosignals. The UE may comprise radio communication device, target device,device to device (D2D) UE, machine type UE or UE capable of machine tomachine communication (M2M), a sensor equipped with UE, iPAD, Tablet,mobile terminals, smart phone, laptop embedded equipped (LEE), laptopmounted equipment (LME), USB dongles, Customer Premises Equipment (CPE),etc.

In some embodiments, network node 120 may include any type of networknode such as a base station, radio base station, base transceiverstation, base station controller, network controller, evolved Node B(eNB), Node B, gNB, multi-RAT base station, Multi-cell/multicastCoordination Entity (MCE), relay node, access point, radio access point,Remote Radio Unit (RRU) Remote Radio Head (RRH), a core network node(e.g., MME, SON node, a coordinating node, etc.), or even an externalnode (e.g., 3rd party node, a node external to the current network),etc.

Wireless signals 130 may include both downlink transmissions (from radionetwork node 120 to wireless devices 110) and uplink transmissions (fromwireless devices 110 to radio network node 120). Wireless signals 130may include synchronization signals and reference signals in addition todata and control channels. Wireless signals 130 may include systeminformation.

Each network node 120 may have a single transmitter or multipletransmitters for transmitting wireless signals 130 to wireless devices110. In some embodiments, network node 120 may comprise a multi-inputmulti-output (MIMO) system. Similarly, each wireless device 110 may havea single receiver or multiple receivers for receiving signals 130 fromnetwork nodes 120.

Network 100 may include carrier aggregation. For example, wirelessdevice 110 may be served by both network node 120 a and 120 b andcommunicate wireless signals 130 with both network node 120 a and 120 b.

Network node 120 may operate in a licensed frequency spectrum, such asan LTE spectrum. Network node 120 may also operate in an unlicensedfrequency spectrum, such as a 5 GHz Wi-Fi spectrum. In an unlicensedfrequency spectrum, network node 120 may coexist with other devices suchas IEEE 802.11 access points and terminals. To share the unlicensedspectrum, network node 120 may perform listen before talk (LBT)protocols before transmitting or receiving wireless signals 130.Wireless device 110 may also operate in one or both of licensed orunlicensed spectrum and in some embodiments may also perform LBTprotocols before transmitting wireless signals 130. Both network node120 and wireless device 110 may also operate in licensed sharedspectrum.

For example, network node 120 a may operate in a licensed spectrum andnetwork node 120 b may operate in an unlicensed spectrum. Wirelessdevice 110 may operate in both licensed and unlicensed spectrum. Inparticular embodiments, network nodes 120 a and 120 b may beconfigurable to operate in a licensed spectrum, an unlicensed spectrum,a licensed shared spectrum, or any combination. Although the coveragearea of cell 115 b is illustrated as included in the coverage area ofcell 115 a, in particular embodiments the coverage areas of cells 115 aand 115 b may overlap partially, or may not overlap at all.

In certain embodiments, network nodes 125 may interface with a radionetwork controller (RNC). The radio network controller may controlnetwork nodes 120 and may provide certain radio resource managementfunctions, mobility management functions, and/or other suitablefunctions. In certain embodiments, the functions of the radio networkcontroller may be included in network node 120. The radio networkcontroller may interface with a core network node (CN), such as corenetwork node 320.

Core network node 320 may comprise an EPS core network node, a 5GS corenetwork node, or any other suitable type of core network node. In someembodiments network node 120 may be connected to one or more corenetwork nodes (e.g., core network nodes 320 a and 320 b). Core networknodes 320 a and 320 b may of the same or different network types.

In certain embodiments, the radio network controller may interface withcore network node 320 via an interconnecting wired or wireless network.The interconnecting network may refer to any interconnecting systemcapable of transmitting audio, video, signals, data, messages, or anycombination of the preceding. The interconnecting network may includeall or a portion of a public switched telephone network (PSTN), a publicor private data network, a local area network (LAN), a metropolitan areanetwork (MAN), a wide area network (WAN), a local, regional, or globalcommunication or computer network such as the Internet, a wireline orwireless network, an enterprise intranet, or any other suitablecommunication link, including combinations thereof.

In some embodiments, core network node 320 may manage the establishmentof communication sessions and various other functionalities for wirelessdevices 110. Examples of core network node 320 may include mobileswitching center (MSC), mobility management entity (MME), servinggateway (SGW), packet data network gateway (PGW), operation andmaintenance (O&M), operations support system (OSS), SON, positioningnode (e.g., Enhanced Serving Mobile Location Center, (E-SMLC)), MDTnode, etc. Wireless devices 110 may exchange certain signals with corenetwork node 320 using the non-access stratum layer. In non-accessstratum signaling, signals between wireless devices 110 and core networknode 320 may be transparently passed through the radio access network.In certain embodiments, network nodes 120 may interface with one or morenetwork nodes 120 over an internode interface, such as, for example, anX2 interface.

In some embodiments, network node 120 broadcasts system information.Wireless devices 110 a and 110 b may receive the system information todetermine a network configuration. Wireless devices 110 a and 110 b mayuse the network configuration to connect to the network.

According to some embodiments, wireless device 110 may acquire systeminformation associated with core network 320 by receiving systeminformation (e.g., system information block one (SIB1), systeminformation block two (SIB2), etc.) from network node 120. Network node120 is connected to one or more core networks 320. The systeminformation includes an indication of a network type (e.g., EPS, 5GS,etc.) for each core network 320. Wireless devices 110 determines acapability of wireless device 110 for connecting to the plurality ofnetwork types. For example, wireless device 110 determines whether itcan connect to EPS only, 5GS only, both EPS and 5GS, etc. Wirelessdevice 110 determines whether to connect to a particular core network320 based on the network type and the capability of wireless device 110.In particular embodiments, the indication of the network type comprisesa list of PLMNs connected to the network node and an indication ofnetwork types supported by each PLMN.

In particular embodiments, determining whether to connect to a corenetwork 320 comprises determining not to connect to any of the one ormore core networks 320. For example, based on the capabilities ofwireless device 110 (e.g., EPS only), wireless device 110 may not beable to connect to any core network 320 (e.g., 5GS only). In which case,wireless device 110 may connect to another network node 120.

In particular embodiments, wireless device 110 is capable of connectingto a 5GS core network type. Wireless device 110 may interpret one ormore parameters of the received system information differently for 5GSthan for EPS or may acquire 5GS specific system information blocks.Interpreting one or more parameters of the received system informationdifferently for 5GS may comprise obtaining an indication (e.g.,receiving dedicated or broadcast signaling from network node 120) thatone or more information elements of the system information are to beinterpreted according to 5GS. Obtaining the indication that one or moreinformation elements are to be interpreted according to 5GS may comprisedetermining that wireless device 110 is connected to a 5GS core network320.

According to some embodiments, network node 120 provides systeminformation (e.g. SIB1, SIB2, etc.) associated with core network 320 bydetermining network node 120 is connected to one or more core networks320. Network node 120 transmits system information that includes anindication of a network type (e.g., EPS, 5GS, etc.) for each corenetwork 320. The indication of the network type may comprise a list ofidentifiers of one or more PLMNs connected to network node 120 and anindication of one or more network types supported by each PLMN.

In particular embodiments, core network 320 is a 5GS core network. Thesystem information for core network 320 includes parameters that have adifferent meaning with respect to 5GS than with respect to EPS. Thesystem information may include 5GS specific system information blocks.

In particular embodiments, network node 120 transmits an indication(e.g., dedicated signaling or broadcast signaling) that one or moreinformation elements of the system information are to be interpretedaccording to 5GS. The system information with respect to EPS and 5GScore networks is described in more detail below.

In wireless network 100, each radio network node 120 may use anysuitable radio access technology, such as long term evolution (LTE),LTE-Advanced, NR, UMTS, HSPA, GSM, cdma2000, WiMax, WiFi, and/or othersuitable radio access technology. Wireless network 100 may include anysuitable combination of one or more radio access technologies. Forpurposes of example, various embodiments may be described within thecontext of certain radio access technologies. However, the scope of thedisclosure is not limited to the examples and other embodiments coulduse different radio access technologies.

As described above, embodiments of a wireless network may include one ormore wireless devices and one or more different types of radio networknodes capable of communicating with the wireless devices. The networkmay also include any additional elements suitable to supportcommunication between wireless devices or between a wireless device andanother communication device (such as a landline telephone). A wirelessdevice may include any suitable combination of hardware and/or software.For example, in particular embodiments, a wireless device, such aswireless device 110, may include the components described below withrespect to FIG. 5A. Similarly, a network node may include any suitablecombination of hardware and/or software. For example, in particularembodiments, a network node, such as network node 120, may include thecomponents described below with respect to FIG. 6A. A core network nodemay include any suitable combination of hardware and/or software. Forexample, in particular embodiments, a core network node, such as corenetwork node 320, may include the components described below withrespect to FIG. 7 .

Particular embodiments indicate support for 5GC per PLMN. In oneexample, the SIB1 PLMN list is extended with additional informationelement (IE) indicating support for 5GC. An advantage of this example isthat the UE only needs to read SIB1 to determine which core network(s)are supported for each PLMN. In another example, a separate list IE canbe added in SIB2, which is interpreted by the UE as per PLMN (i.e.,combining the information in SIB2 with the PLMN list in SIB1).

An LTE eNB broadcasts information about which PLMNs are available inSIB1 in the ‘PLMN-IDENTITY-LIST’ described in 3GPP TS 36.331, “EvolvedUniversal Terrestrial Radio Access (E-UTRA); Radio Resource Control(RRC); Protocol specification (Release 14); Protocol specification”,September 2016, which is hereby incorporated. The ‘PLMN-IDENTITY-LIST’contains the PLMN IDs of the PLMNs to which the eNB is connected. The‘PLMN-IDENTITY-LIST’ is limited to a maximum of six PLMN IDs. To informthe UEs about which core networks are available for a given PLMN, someembodiments extend the ‘PLMN-IDENTITY-LIST’ with an additionalinformation element (IE) per PLMN ID, to indicate if, for thecorresponding PLMN, the LTE eNB is connected to EPC only or to both EPCand 5GC.

SIB2 in LTE includes a list with dedicated barring information for eachPLMN, namely AC-BarringPerPLMN as described in TS 36.331. Accordingly,some embodiments inform a UE about the available core networks for eachPLMN by extending the AC-BarringPerPLMN list with a new IE per PLMN(e.g., an additional entry in the barring list) that indicates theavailable core networks (i.e., EPC only or both EPC and 5GC). Anadvantage these embodiments is that the barring information may be usedto perform load balancing between EPC and 5GC within one PLMN. Forexample, if the 5GC is temporarily overloaded, it is possible totemporarily bar 5GC so that all new incoming UEs are forced to attach toEPC.

Some embodiments indicate which system information is relevant for EPSand 5GS. For example, when the LTE eNB is connected to both EPC and5G-CN (5GC) and serves both new and legacy UE, particular embodimentsindicate which system information is applicable when the UE is connectedto EPS or to 5GS.

Particular embodiments may apply the following principles forinterpreting system information. UEs connected to EPC may assume thatall current system information applies. UEs connected to 5G-CN mayassume that all the current system information applies unless anindication is included (in the system information or via dedicatedsignaling), informing the UE that an alternative parameter orinterpretation should be applied. The indication may be per a systeminformation element or per group of system information elements (wholesystem info block). The alternative parameter may be sent in alternativesystem information blocks only read by new UEs (e.g., SIB3alt).

Additionally, 5G UEs may follow specified rules in the specification ora UE may include a configuration indicating which set of existing systeminformation should be followed and which set should be ignored. Whichsystem information blocks should be applied or ignored can be signaledfrom the network using dedicated signaling or broadcasted.

Particular embodiments facilitate 5GS-only cells. To deploy 5GC only LTEnetworks, particular embodiments may set the CellReservedForOperatorUseto Reserved so that legacy UEs ignore the cell/PLMN. The extension fieldto CellReservedForOperatorUse overrides the legacy value and forces UEscapable of only EPC-NAS to reselect to a different cell.

Some embodiments create a new SIB1 instance which can only becomprehended by 5GC capable UEs. The new SIB1 instance may be done witha critical extension to SIB1 (i.e., SIB1-r15) or using a new BCCH-DL-SCHlogical channel (i.e., BCCH-DL-SCH-5GCN).

Some embodiments may indicate in the MasterInformationBlock a parameterthat causes legacy UEs to ignore the cell (e.g., set an invalid valuefor the dl-Bandwidth). A MasterInformationBlock is illustrated below:

MasterInformationBlock -- ASN1START MasterInformationBlock ::= SEQUENCE{  dl-Bandwidth ENUMERATED {  n6, n15, n25, n50, n75, n100}, phich-Config PHICH-Config,  systemFrameNumber  BIT STRING (SIZE (8)), schedulingInfoSIB1-BR-r13  INTEGER (0..31),  spare BIT STRING (SIZE(5)) } -- ASN1STOP

Using an existing parameter to bar the cell for operator use preventslegacy UEs from camping or connecting to the cell. 5G UEs supporting 5GSignore the parameter. Some embodiments include a parameter to indicateif the cell is also barred for 5G UEs supporting 5GS.

Particular embodiments include methods in a wireless device and anetwork node. Examples are illustrated in FIGS. 3 and 4 , respectively.

FIG. 3 is a flow diagram of an example method in a user equipment,according to some embodiments. Method 300 includes steps for acquiringsystem information associated with a core network. In particularembodiments, one or more steps of FIG. 3 may be performed by wirelessdevice 110 of wireless network 100 described with respect to FIG. 2 .

The method begins at step 312, where the user equipment receives systeminformation from a network node. The network node is connected to one ormore core networks. The system information includes an indication of anetwork type for one or more core networks.

For example, wireless device 110 may receive system information fromnetwork node 120 a. Network node 120 a may be connected to core networks320 a and 320 b. Core networks 320 a and 320 b may be an EPS corenetwork type, a 5GS core network type, or any other suitable corenetwork type. Network node 120 a may broadcast system information, suchas SIB1, SIB2, or any other suitable system information, that includesan indication of the network type of core networks 320 a and 320 b(e.g., core network 320 a may be an EPS core network type and 320 b maybe a 5GS core network type, both core networks 320 a and 320 b may be a5GS core network type, both core networks 320 a and 320 b may be an EPScore network type, etc.).

In particular embodiments, the indication of the network type comprisesa list of PLMNs connected to network node 120 a and an indication ofnetwork types supported by each PLMN. In one example, the SIB1 PLMN listis extended with an additional information element (IE) indicatingsupport for 5GS. An advantage of this example is that wireless device110 only needs to read SIB1 to determine which core network(s) 320 aresupported for each PLMN. In another example, a separate list IE can beadded in SIB2. Wireless device 110 interprets the list as per PLMN(i.e., combining the information in SIB2 with the PLMN list in SIB1).

In another example, the indication of the network type comprises a listwith dedicated barring information for each PLMN, such as theAC-BarringPerPLMN list. Network node 120 a informs wireless device 110about available core networks 320 for each PLMN by extending theAC-BarringPerPLMN list with a new IE per PLMN (e.g., an additional entryin the barring list) that indicates the available core networks 320(i.e., EPC only or both EPC and 5GC). An advantage these embodiments isthat the barring information may be used to perform load balancingbetween EPC and 5GC within one PLMN. For example, if the 5GC istemporarily overloaded, it is possible to temporarily bar 5GC so thatall new incoming wireless devices 110 are forced to attach to EPC.

At step 314, the user equipment determines a capability of the wirelessdevice for connecting to the plurality of network types. For example,wireless device 110 may determine that it capable of connecting to anEPS core network 320, a 5GS core network 320, both an EPS and a 5GS corenetwork 320, etc. Wireless device 110 may be preconfigured with itscapabilities.

At step 316, the user equipment determines whether to connect to a corenetwork based on the network type and the capability of the wirelessdevice. For example, wireless device 110 may determine that it iscapable of connecting to a 5GS core network and based on the indicationin the system information, wireless device 110 knows that core network320 b is a 5GS core network. Wireless device 110 may decide to connectto core network 320 b.

As another example, wireless device 110 may determine that it is onlycapable of connecting to an EPS core network and, based on theindication in the system information, wireless device 110 knows thatcore network 320 a is an EPS core network. Wireless device 110 maydecide to connect to core network 320 a.

As another example, wireless device 110 may determine that it is onlycapable of connecting to an EPS core network and, based on theindication in the system information, wireless device 110 knows thatcore networks 320 a and 320 b are both 5GS core networks. Wirelessdevice 110 may reselect to network node 120 b and repeat steps 312-316to determine whether wireless device 110 can connect to a core networkattached to network node 120 b.

In some embodiments, one or more parameters of system information may beinterpreted differently for 5GS than for EPS. Some embodiments indicatewhich system information is relevant for EPS and 5GS. For example, whennetwork node 120 a is connected to both EPS and 5GS, particularembodiments indicate which system information is applicable whenwireless device 110 is connected to EPS or to 5GS.

Particular embodiments may apply the following principles forinterpreting system information. Wireless device 110 connected to EPSmay assume that all current system information applies. Wireless device110 connected to 5GS may assume that all the current system informationapplies unless an indication is included (in the system information orvia dedicated signaling), informing wireless device 110 that analternative parameter or interpretation should be applied. Theindication may be per a system information element or per group ofsystem information elements (whole system info block). The alternativeparameter may be sent in alternative system information blocks only readby a 5G wireless device 110 (e.g., SIB3alt).

Additionally, 5G wireless device 110 may follow specified rules in thespecification or 5G wireless device 110 may include a configurationindicating which set of existing system information should be followedand which set should be ignored. Which system information blocks shouldbe applied or ignored can be signaled from the network using dedicatedsignaling or broadcasted.

Modifications, additions, or omissions may be made to method 300illustrated in FIG. 3 . Additionally, one or more steps in method 300may be performed in parallel or in any suitable order.

FIG. 4 is a flow diagram of an example method in a network node,according to some embodiments. Method 400 includes steps for providingsystem information associated with a core network. In particularembodiments, one or more steps of FIG. 4 may be performed by networknode 120 of wireless network 100 described with respect to FIG. 2 .

The method begins at step 412, where the network node determines thenetwork node is connected to one or more core networks. For example,network node 120 a determines that it is connected to core networks 320a and 320 b. Core networks 320 a and 320 b may comprise any of the corenetwork types described above with respect to FIG. 3 .

At step 414, the network node transmits system information that includesan indication of a network type for each core network. For example,network node 120 a may transmit system information as described abovewith respect to step 312 of FIG. 3 .

At step 416, the network node may transmit an indication that one ormore information elements of the system information are to beinterpreted according to 5GS. For example, network node 120 a maytransmit an indication as described with respect to step 316 of FIG. 3 .

Modifications, additions, or omissions may be made to method 400illustrated in FIG. 4 . Additionally, one or more steps in method 400may be performed in parallel or in any suitable order.

FIG. 5A is a block diagram illustrating an example embodiment of awireless device. The wireless device is an example of the wirelessdevices 110 illustrated in FIG. 2 . In particular embodiments, thewireless device is capable of receiving system information (e.g., systeminformation block one (SIB1), system information block two (SIB2), etc.)from a network node. The network node is connected to one or more corenetworks, and the system information includes an indication of a networktype (e.g., EPS, 5GS, etc.) for each core network. The wireless deviceis capable of determining a capability of the wireless device forconnecting to the plurality of network types, and determining whether toconnect to a core network based on the network type and the capabilityof the wireless device.

Particular examples of a wireless device include a mobile phone, a smartphone, a PDA (Personal Digital Assistant), a portable computer (e.g.,laptop, tablet), a sensor, a modem, a machine type (MTC) device/machineto machine (M2M) device, laptop embedded equipment (LEE), laptop mountedequipment (LME), USB dongles, a device-to-device capable device, avehicle-to-vehicle device, or any other device that can provide wirelesscommunication. The wireless device includes transceiver 1110, processingcircuitry 1120, memory 1130, and power source 1140. In some embodiments,transceiver 1110 facilitates transmitting wireless signals to andreceiving wireless signals from wireless network node 120 (e.g., via anantenna), processing circuitry 1120 executes instructions to providesome or all of the functionality described herein as provided by thewireless device, and memory 1130 stores the instructions executed byprocessing circuitry 1120. Power source 1140 supplies electrical powerto one or more of the components of wireless device 110, such astransceiver 1110, processing circuitry 1120, and/or memory 1130.

Processing circuitry 1120 includes any suitable combination of hardwareand software implemented in one or more integrated circuits or modulesto execute instructions and manipulate data to perform some or all ofthe described functions of the wireless device. In some embodiments,processing circuitry 1120 may include, for example, one or morecomputers, one more programmable logic devices, one or more centralprocessing units (CPUs), one or more microprocessors, one or moreapplications, and/or other logic, and/or any suitable combination of thepreceding. Processing circuitry 1120 may include analog and/or digitalcircuitry configured to perform some or all of the described functionsof wireless device 110. For example, processing circuitry 1120 mayinclude resistors, capacitors, inductors, transistors, diodes, and/orany other suitable circuit components.

Memory 1130 is generally operable to store computer executable code anddata. Examples of memory 1130 include computer memory (e.g., RandomAccess Memory (RAM) or Read Only Memory (ROM)), mass storage media(e.g., a hard disk), removable storage media (e.g., a Compact Disk (CD)or a Digital Video Disk (DVD)), and/or or any other volatile ornon-volatile, non-transitory computer-readable and/orcomputer-executable memory devices that store information.

Power source 1140 is generally operable to supply electrical power tothe components of wireless device 110. Power source 1140 may include anysuitable type of battery, such as lithium-ion, lithium-air, lithiumpolymer, nickel cadmium, nickel metal hydride, or any other suitabletype of battery for supplying power to a wireless device.

Other embodiments of the wireless device may include additionalcomponents (beyond those shown in FIG. 5A) responsible for providingcertain aspects of the wireless device's functionality, including any ofthe functionality described above and/or any additional functionality(including any functionality necessary to support the solution describedabove).

FIG. 5B is a block diagram illustrating example components of wirelessdevice 110. The components may include receiving module 1150 anddetermining module 1152.

Receiving module 1150 may perform the receiving functions of wirelessdevice 110. For example, receiving module 1150 may receive systeminformation and/or signaling for how to interpret system information asdescribed in any of the embodiments or examples above (e.g., steps 312and/or 316 of FIG. 3 ). In certain embodiments, receiving module 1150may include or be included in processing circuitry 1120. In particularembodiments, receiving module 1150 may communicate with determiningmodule 1152.

Determining module 1152 may perform the determining functions ofwireless device 110. For example, determining module 1152 may determinecapabilities of a wireless device and/or determine whether to connect toa particular core network according to any of the examples describedabove (e.g., steps 314 and 316 of FIG. 3 ). In certain embodiments,determining module 1152 may include or be included in processingcircuitry 1120. In particular embodiments, determining module 1152 maycommunicate with receiving module 1150.

FIG. 6A is a block diagram illustrating an example embodiment of anetwork node. The network node is an example of network node 120illustrated in FIG. 2 . In particular embodiments, the network node iscapable of determining the network node is connected to one or more corenetworks, and transmitting system information (e.g., SIB1, SIB2, etc.)that includes an indication of a network type (e.g., EPS, 5GS, etc.) foreach core network.

Network node 120 can be an eNodeB, a nodeB, gNB, a base station, awireless access point (e.g., a Wi-Fi access point), a low power node, abase transceiver station (BTS), a transmission point or node, a remoteRF unit (RRU), a remote radio head (RRH), or other radio access node.The network node includes at least one transceiver 1210, at least oneprocessing circuitry 1220, at least one memory 1230, and at least onenetwork interface 1240. Transceiver 1210 facilitates transmittingwireless signals to and receiving wireless signals from a wirelessdevice, such as wireless devices 110 (e.g., via an antenna); processingcircuitry 1220 executes instructions to provide some or all of thefunctionality described above as being provided by a network node 120;memory 1230 stores the instructions executed by processing circuitry1220; and network interface 1240 communicates signals to backend networkcomponents, such as a gateway, switch, router, Internet, Public SwitchedTelephone Network (PSTN), controller, and/or other network nodes 120.Processing circuitry 1220 and memory 1230 can be of the same types asdescribed with respect to processing circuitry 1120 and memory 1130 ofFIG. 5A above.

In some embodiments, network interface 1240 is communicatively coupledto processing circuitry 1220 and refers to any suitable device operableto receive input for network node 120, send output from network node120, perform suitable processing of the input or output or both,communicate to other devices, or any combination of the preceding.Network interface 1240 includes appropriate hardware (e.g., port, modem,network interface card, etc.) and software, including protocolconversion and data processing capabilities, to communicate through anetwork.

Other embodiments of network node 120 include additional components(beyond those shown in FIG. 6A) responsible for providing certainaspects of the network node's functionality, including any of thefunctionality described above and/or any additional functionality(including any functionality necessary to support the solution describedabove). The various different types of network nodes may includecomponents having the same physical hardware but configured (e.g., viaprogramming) to support different radio access technologies, or mayrepresent partly or entirely different physical components.

FIG. 6B is a block diagram illustrating example components of networknode 120. The components may include determining module 1250 andtransmitting module 1252.

Determining module 1250 may perform the determining functions of networknode 120. For example, determining module 1250 may determine that it isconnected to one or more core networks as described in any of theembodiments or examples above (e.g., step 412 of FIG. 4 ). In certainembodiments, determining module 1250 may include or be included inprocessing circuitry 1220. In particular embodiments, determining module1250 may communicate with transmitting module 1252.

Transmitting module 1252 may perform the transmitting functions ofnetwork node 120. For example, transmitting module 1252 may transmitsystem information and/or an indication of how to interpret systeminformation according to any of the examples described above (e.g.,steps 414 and 416 of FIG. 4 ). In certain embodiments, transmittingmodule 1252 may include or be included in processing circuitry 1220. Inparticular embodiments, transmitting module 1252 may communicate withdetermining module 1250.

FIG. 7 is a block schematic of an example core network node 320, inaccordance with certain embodiments. In particular embodiments, the corenetwork node may comprise an EPS core network node, a 5GS core networknode, or any other suitable type of core network node.

Examples of core network nodes can include an Evolved Serving MobileLocation Centre (E-SMLC), a mobile switching center (MSC), a servingGPRS support node (5GSN), a mobility management entity (MME), a radionetwork controller (RNC), a base station controller (BSC), an access andmobility management function (AMF), and so on. The core network nodeincludes processing circuitry 620, memory 630, and network interface640. In some embodiments, processing circuitry 620 executes instructionsto provide some or all of the functionality described above as beingprovided by the network node, memory 630 stores the instructionsexecuted by processing circuitry 620, and network interface 640communicates signals to any suitable node, such as a gateway, switch,router, Internet, Public Switched Telephone Network (PSTN), networknodes 120, radio network controllers or core network nodes 320, etc.

Processing circuitry 620 may include any suitable combination ofhardware and software implemented in one or more modules to executeinstructions and manipulate data to perform some or all of the describedfunctions of the core network node. In some embodiments, processingcircuitry 620 may include, for example, one or more computers, one ormore central processing units (CPUs), one or more microprocessors, oneor more applications, and/or other logic.

Memory 630 is generally operable to store instructions, such as acomputer program, software, an application including one or more oflogic, rules, algorithms, code, tables, etc. and/or other instructionscapable of being executed by a processor. Examples of memory 630 includecomputer memory (for example, Random Access Memory (RAM) or Read OnlyMemory (ROM)), mass storage media (for example, a hard disk), removablestorage media (for example, a Compact Disk (CD) or a Digital Video Disk(DVD)), and/or or any other volatile or non-volatile, non-transitorycomputer-readable and/or computer-executable memory devices that storeinformation.

In some embodiments, network interface 640 is communicatively coupled toprocessing circuitry 620 and may refer to any suitable device operableto receive input for the network node, send output from the networknode, perform suitable processing of the input or output or both,communicate to other devices, or any combination of the preceding.Network interface 640 may include appropriate hardware (e.g., port,modem, network interface card, etc.) and software, including protocolconversion and data processing capabilities, to communicate through anetwork.

Other embodiments of the network node may include additional componentsbeyond those shown in FIG. 7 that may be responsible for providingcertain aspects of the core network node's functionality, including anyof the functionality described above and/or any additional functionality(including any functionality necessary to support the solution describedabove).

Some embodiments of the disclosure may provide one or more technicaladvantages. Some embodiments may benefit from some, none, or all ofthese advantages. Other technical advantages may be readily ascertainedby one of ordinary skill in the art. For example, in some embodiments aUE can unambiguously interpret the content of the system informationwhen acquiring system information from a cell serving EPS and 5GSsimultaneously. This may avoid incorrect UE understanding of networkcapabilities. Particular embodiments that indicate support for 5GC on aper PLMN basis facilitate different operators sharing the same RAN node.Upgrading to 5GC support may be performed at different times. Requiringall operators to upgrade at the same time is more challenging, and thusundesirable.

Although this disclosure has been described in terms of certainembodiments, alterations and permutations of the embodiments will beapparent to those skilled in the art. Although some embodiments havebeen described with reference to certain radio access technologies, anysuitable radio access technology (RAT) or combination of radio accesstechnologies may be used, such as long term evolution (LTE),LTE-Advanced, NR, UMTS, HSPA, GSM, cdma2000, WiMax, WiFi, etc.Accordingly, the above description of the embodiments does not constrainthis disclosure. Other changes, substitutions, and alterations arepossible without departing from the scope of this disclosure.

Abbreviations:

-   -   3GPP 3rd Generation Partnership Project    -   5GC Fifth Generation System    -   5GC Fifth Generation Core    -   AS Access Stratum    -   CA Carrier Aggregation    -   CC Component Carrier    -   CN Core Network    -   eMTC enhanced Machine Type Communications    -   eMTC-U enhanced Machine Type Communications for Unlicensed Band    -   eNB Evolved Node B    -   eNodeB Evolved Node B    -   EPC Evolved Packet Core    -   EPS Evolved Packet System    -   E-SMLC Evolved Serving Mobile Location Center    -   FeMTC Further enhanced MTC    -   FDD Frequency Division Duplex    -   gNB Fifth Generation Node B    -   GNSS Global Navigation Satellite System    -   ID Identifier    -   IoT Internet of Things    -   LBT Listen Before Talk    -   LPP LTE Positioning Protocol    -   LTE Long-Term Evolution    -   MF MuLTEfire    -   MME Mobility Management Entity    -   MSC Mobile Switching Center    -   MTC Machine Type Communication    -   NAS Non Access Stratum    -   NB-IoT NarrowBand-IoT    -   NB-IoT-U Narrow-band Internet of Things for Unlicensed Band    -   NGS Next Generation System    -   NR New Radio    -   NW Network    -   OTDOA Observed Time Difference of Arrival    -   PBCH Physical Broadcast Channel    -   PCID Physical Cell Identity    -   PCC Primary Component Carrier    -   PCell Primary Cell    -   PDU Protocol Data Unit    -   PGW Packet Data Network Gateway    -   PRB Physical Resource Block    -   PSD Power Spectral Density    -   RAT Radio Access Technology    -   RAN Radio Access Network    -   RRC Radio Resource Control    -   RSRP Reference Signal Received Power    -   RSRQ Reference Signal Received Quality    -   RSTD Reference Signal Time Difference    -   SCC Secondary Component Carrier    -   SCell Secondary Cell    -   SFN System Frame Number    -   SGW Serving Gateway    -   SLA Service Level Agreement    -   TDD Time Division Duplex    -   TDOA Time Difference Of Arrival    -   TOA Time Of Arrival    -   UE User Equipment    -   UMTS Universal Mobile Telecommunications System    -   UTDOA Uplink Time Difference of Arrival

The invention claimed is:
 1. A method for use in a wireless device ofacquiring system information associated with a core network, the methodcomprising: receiving system information from a network node, thenetwork node connected to one or more core networks, the systeminformation including an indication of a network type for each corenetwork of the one or more core networks, wherein each core network iseither an enhanced packet system (EPS) core network or a fifthgeneration system (5GS) core network; determining a capability of thewireless device for connecting to a EPS core network, a 5GS corenetwork, or both; and determining whether to connect to a core networkof the one or more core networks based on the network type of the corenetwork and the capability of the wireless device for connecting to theplurality of network types.
 2. The method of claim 1, wherein theindication of the network type for each core network of the one or morecore networks is received in system information block one (SIB1) orsystem information block two (SIB2).
 3. The method of claim 1, whereindetermining whether to connect to a core network of the one or more corenetworks comprises determining not to connect to any of the one or morecore networks; and the method further comprises connecting to adifferent network node.
 4. The method of claim 1, wherein determiningthe capability of the wireless device for connecting to the plurality ofnetwork types comprises determining the wireless device is capable ofconnecting to a 5GS core network type; and the method further comprisesinterpreting one or more parameters of the received system informationdifferently for 5GS than for EPS.
 5. The method of claim 4, whereininterpreting one or more parameters of the received system informationdifferently for 5GS than for EPS comprises ignoring an EPS barringparameter and determining whether to connect to a core network of theone or more core networks comprises evaluating a 5GS barring parameter.6. The method of claim 4, wherein interpreting one or more parameters ofthe received system information differently for 5GS comprises obtainingan indication that one or more information elements of the systeminformation are to be interpreted according to 5GS.
 7. The method ofclaim 6, wherein obtaining the indication that one or more informationelements are to be interpreted according to 5GS comprises at least oneof receiving dedicated signaling or broadcast signaling from the networknode.
 8. The method of claim 6, wherein obtaining the indication thatone or more information elements are to be interpreted according to 5GScomprises determining that the wireless device is connected to a 5GScore network.
 9. The method of claim 4, wherein determining thecapability of the wireless device for connecting to the plurality ofnetwork types comprises determining the wireless device is capable ofconnecting to a 5GS core network type; and the method further comprisesacquiring 5GS specific system information blocks.
 10. A wireless devicecapable of acquiring system information associated with a core network,the wireless device comprising processing circuitry operable to: receivesystem information from a network node, the network node connected toone or more core networks, the system information including anindication of a network type for each core network of the one or morecore networks, wherein each core network is either an enhanced packetsystem (EPS) core network or a fifth generation system (5GS) corenetwork; determine a capability of the wireless device for connecting toa EPS core network, a 5GS core network, or both; and determine whetherto connect to a core network of the one or more core networks based onthe network type of the core network and the capability of the wirelessdevice for connecting to the plurality of network types.
 11. Thewireless device of claim 10, the processing circuitry is operable toreceive the indication of the network type for each core network of theone or more core networks in system information block one (SIB1) orsystem information block two (SIB2).
 12. The wireless device of claim10, wherein when the processing circuitry determines not to connect toany of the one or more core networks, the processing circuitry isfurther operable to connect to a different network node.
 13. Thewireless device of claim 12, wherein when the processing circuitrydetermines the wireless device is capable of connecting to a 5GS corenetwork type, the processing circuitry is further operable to interpretone or more parameters of the received system information differentlyfor 5GS than for EPS.
 14. The wireless device of claim 13, wherein theprocessing circuitry is operable to interpret one or more parameters ofthe received system information differently for 5GS than for EPS byignoring an EPS barring parameter and is operable to determine whetherto connect to a core network of the one or more core networks byevaluating a 5GS barring parameter.
 15. The wireless device of claim 13,wherein the processing circuitry is operable to interpret one or moreparameters of the received system information differently for 5GS byobtaining an indication that one or more information elements of thesystem information are to be interpreted according to 5GS.
 16. Thewireless device of claim 13, wherein the processing circuitry isoperable to obtain the indication that one or more information elementsare to be interpreted according to 5GS by at least one of receivingdedicated signaling or broadcast signaling from the network node. 17.The wireless device of claim 13, wherein the processing circuitry isoperable to obtain the indication that one or more information elementsare to be interpreted according to 5GS by determining that the wirelessdevice is connected to a 5GS core network.
 18. The wireless device ofclaim 12, wherein when the processing circuitry determines the wirelessdevice is capable of connecting to a 5GS core network type, theprocessing circuitry is further operable to acquire 5GS specific systeminformation blocks.
 19. A method for use in a network node of providingsystem information associated with a core network, the methodcomprising: determining the network node is connected to one or morecore networks; and transmitting system information, the systeminformation including an indication of a network type for each corenetwork of the one or more core networks wherein each core network iseither an enhanced packet system (EPS) core network or a fifthgeneration system (5GS) core network.
 20. The method of claim 19,wherein the indication of the network type for each core network of theone or more core networks is in system information block one (SIB1) orsystem information block two (SIB2).
 21. The method of claim 19, whereina core network of the one or more core networks is a 5GS core networkand the system information for the core network includes parameters thathave a different meaning with respect to 5GS than with respect to EPS.22. The method of claim 19, wherein a core network of the one or morecore networks is a 5GS core network and the system information for thecore network includes 5GS specific system information blocks.
 23. Themethod of claim 22, further comprising transmitting an indication thatone or more information elements of the system information are to beinterpreted according to 5GS.
 24. The method of claim 23, whereintransmitting the indication that one or more information elements are tobe interpreted according to 5GS comprises transmitting dedicatedsignaling or transmitting broadcast signaling.